On top of the world

Robert Macfarlane's fascinating personal account of the appeal and terrors of high-altitude climbing won him the Guardian First Book award last night. He tells Oliver Burkeman how he fell in love with the mountains

Like many people who fall in love with mountains, Robert Macfarlane left a part of himself behind there. Specifically, he left the pads of three fingers, destroyed by frostbite, which he summarily removed with a penknife and burned, he writes, "with a crackle and the smell of charred flesh". Then again, the Everest explorer Howard Somervell left a chunk of his frozen larynx behind - he was on the verge of choking to death until he hammered on his chest and coughed it up - and the last thing Macfarlane would want you to think is that he's posturing about a few bits of finger. "I'm absolutely not a serious mountaineer," says the 27-year-old author of Mountains of the Mind, which won the Guardian First Book Award last night. "But I wanted to explain how mountains could come to possess somebody."

His own brushes with death at high altitudes, and with what he calls "that fizzing, nauseous, faintly erotic feeling of real terror", read frighteningly enough. At one memorable point, he is crossing a snow bridge in the Alps when it starts to collapse underneath him, crumbling into thin air. But he won't even boast about that. "The one line that makes me cringe more than any other comes where I say 'Between my legs I could see a whole lot of nothing'," he says. "It seems so embarrassingly ripe for psychoanalysis."

Serious climbers, it seems, have been getting their safety ropes in a twist over Mountains of the Mind, which may help explain Macfarlane's self-deprecation. The book, subtitled "a history of a fascination", deploys a deft blend of memoir and monograph to explain how mountains, and their mysterious pull, are products of the physical world and the human imagination. "They do not kill deliberately, nor do they deliberately please," he writes. They are "only contingencies of geology" - and yet people give their lives for love of them as a consequence of how they have been "imagined into existence down the centuries".

Some hardcore mountaineers, though, seem to be offended that he had the temerity to address the matter in the first place. The Nottingham-born Macfarlane isn't a pro: he has a day job - remarkable, given his age - as a fellow of Emmanuel College, Cambridge, where he teaches English and where, what with the general East Anglian-ness of it all, mountains are strictly products of the imagination.

"He has begun the process of putting himself about as an 'authority'," sniffed a reviewer in one mountaineering magazine - a characteristic dismissal that contrasted radically with the glowing response of critics in the mainstream press. "The danger of this approach is that you get spread too thin and you start having opinions about things you know little about."

That professionals hold no monopoly on the modern romanticisation of mountains, though, is a big part of Macfarlane's point. "Mountaineers are a very fractious community," he says diplomatically, ensconced in an armchair at Emmanuel. "This is a book about Everyman." In his case, mountains proved to be the source of an identity. "I come from the middle of the middle class in the middle of Middle England, and that disenfranchises a person of interesting cultural history," he says. "Fortunately I got taken up mountains, which gave me something to talk about at parties."

The resulting work makes no pretence of trying to join the breathless, adrenaline-infused canon of modern adventure memoirs: instead, it is a lyrical, often leisurely meditation with some striking imagery (silver mica is "as bright as salmon skin" and Scottish granite, pink and flecked with quartz, is a "geological pate") that only occasionally becomes a little overwrought.

So he was taken aback by the climbing community's aggressive response. "I made the great mistake of going into one of the mountaineering internet chatrooms and finding myself and my book being dissected," he says. "I didn't leave the house for a while after that. But I don't begrudge them their opinions. Once a book gets out, it's public property."

Macfarlane's book abounds with enthusiastic non-professionals. We meet Samuel Taylor Coleridge - poet, junkie and pioneer climber - who finds himself trapped on a precipice of Scafell in the Lake District in 1802. He deals with his potentially fatal situation most unprofessionally, but very Coleridgely: he lies down and enters a state "of almost prophetic Trance and Delight" until he figures out a way to descend.

Then there's the 17th-century playwright John Dennis, capturing precisely the delight in pushing oneself close to the edge: "We walk'd upon the very brink... The sense of all this produc'd different motions in me, viz, a delightful Horrour, a terrible Joy, and at the same time, that I was infinitely pleas'd, I trembled."

Macfarlane wrote the book over the course of a year, three years ago, locked in a Cambridge basement with the lights off. "I became a very fierce and unpleasant person," he recalls. Friends had died on the mountains, and they hung over the writing process like ghosts. But they didn't put him off climbing. "That's the idiocy, or the blindness - that things like this can happen and yet people keep going back and back."

Our romanticisation of mountains, he demonstrates, is only a few hundred years old: before that, they were seen as simply ugly, dangerous, and in the way. Today, overcome by complex daily existences, we hunger for their clarifying power. On the mountains, Macfarlane says, "danger has a very simplifying effect. Life becomes reduced to a series of choices: how do I extricate myself from this situation? How do I conduct myself in a way that would preserve my existence? Life boils down to a series of priorities - food, shelter, warmth, getting to your next point. I find that very exciting and appealing in its simplicity."

But the voluntary pursuit of danger requires a profound selfishness, too - a disregard for loved ones, demonstrated most acutely by George Mallory, whose doomed Everest expedition provides the book's focal point and moving finale. "It was a love triangle, simple as that," Macfarlane argues of Mallory's relationships with his wife Ruth and with Everest - the summit he calls "the greatest of all mountains of the mind".

"Mallory is this extremely intelligent, highly educated, articulate young Edwardian. And yet he doesn't seem able to exercise will in the situation he finds himself in," he says. "His will is puny compared to the historical inheritance that is in him, that is driving him towards this arbitrary point in space: the top of Everest." Back home, Mallory has a wife he loves passionately, and young children. "And yet for this imagined patch of snow he's willing to forego all of that."

After they have read the book's dramatic reconstruction of Mallory's final days, Macfarlane says, "A lot of people have said to me, 'You're in love with Mallory, aren't you?' I say no, but there's clearly at least an analogical relationship between him and me, and him and every mountain lover who comes afterwards."

And yet Mallory's decision to put the mountains in his life before the humans is one Macfarlane finds himself decreasingly able to make. He got married at 23 to another Cambridge academic, Julia, and is now the father of a 10-week-old girl, Lily, two facts that make risking his life on the rockface significantly less appealing.

"My fear threshold plummeted the year I got married," he says. On one occasion, he was on a narrow and perilous rock fin in the Alps, which would have to be "donkey-ridden", with one leg on each side. "I just couldn't do it. I was roped up, and I know these ropes can hold two Land Rovers. And I trusted my climbing companion, and we'd travelled for two days to get there. But I just said: 'I'm sorry. We need to turn round.' And bless him, he turned back with me.

"Not that he had much choice," he adds. "He needed somebody to hold the end of his rope."